1. Field of the Invention
The present invention relates to a battery, and more particularly, to a chemical reaction battery using liquid or gaseous active materials.
2. Description of Related Art
A chemical reaction battery has the arrangement that a pair of positive and negative active materials are provided in contact with an electrolyte. The battery reaction therein is oxidation-reduction reaction with the active materials of positive and negative electrodes. A lead storage battery used as an on-board type battery has been well known as one example of the chemical reaction battery. With the lead storage battery, dilute sulfuric acid (H.sub.2 SO.sub.4(aq)) is used as the electrolyte, lead dioxide (PbO.sub.2) is used as the active material of the positive electrode and lead (Pb) is used as the active material of the negative electrode. These active materials are both solid.
In other examples of the chemical reaction battery, liquid or gaseous active materials in addition to the solid active materials are used.
Daniell battery is well known as the battery using a liquid active material. With this battery, dilute sulfuric acid (H.sub.2 SO.sub.4(aq)) is used as the electrolyte, copper sulfate solution (CuSO.sub.4(aq)) is used as the active material of the positive electrode and solid zinc (Zn) is used as the active material of the negative electrode.
High pressure type nickel-hydrogen storage battery is one example of the battery using a gaseous active material. With this battery, pottasium hydroxide solution (KOH.sub.(aq)) is used as the electrolyte, hydrogen gas (H.sub.2(g)) is used as the active material of the negative electrode, which is absorbed with a platinum (Pt) catalyst electrode, and solid nickel oxyhydrate (NiOOH) is used as the active material of the positive electrode.
Batteries using solid active materials in both the positive and negative electrodes, such as the above-described lead storage battery, have been used widely, because, with the batteries using liquid active materials, such as Daniell battery, the separation of the liquid electrolyte and liquid active materials, and permeation of only the specific ions upon charging and discharging have not been effected sufficiently in spite of the provision of a separator. An unglazed earthware separator, for example, has been known as the separator for the Daniell battery. This separator, however, has the problem that the electrolyte (H.sub.2 SO.sub.4(aq)) and active material solution (CuSO.sub.4(aq)) are mixed together with time to generate self-discharging.
The above-described high pressure type nickel-hydrogen storage battery which uses the gaseous active material needs a pressure-resistant casing or hydrogen-occuludable alloy for storing gas as the active material, such as hydrogen. Consequently, it is difficult to provide inexpensive batteries with simple constructions so as not to be applied to general purposes.
However, in these days when the application of the batteries is expanding, the development of the batteries which use liquid or gaseous active materials and are free from the above-described problems, as well as the batteries which use only the solid active materials, has been demanded for increasing the kinds of the practical batteries and consequently, enlarging the choice thereof.